1. Technical Field
This invention relates to an apparatus for transferring data between digital data processing systems. In particular, this invention relates to an integrated controller capable of controlling high speed data and control transfers between a Micro Channel, a local processor and a data bus.
2. Background Art
Communication of data between data processing systems which are separated in physical location is a common requirement. Central processing units (CPUs) of one computer need to communicate with CPUs of other computers. Likewise, peripheral equipment needs to communicate with a host computer
In data communications technology, typically data is communicated in frames having various layers or levels governed by protocols. The data typically consists of a command layer which may include addresses and instructions followed by data. Relatively large blocks of data can be transmitted by data communications technology at a very high rate. What slows down data communications is processor time needed to process the data into frames and handle the protocols of the various layers.